[R] Evaluating a string

[Joshua Wiley]

Hello Jonathan,

You can use eval() and parse(), although there may be better ways of
getting to your end goal (assuming you have not inherited a series of
character strings held in objects that should be run as commands).  At
any rate, this works:

a <- 3
b <- 2
operator <- "-"
statement_string <- paste(a, operator, b, sep="")
eval(parse(text = statement_string))

Best regards,

Josh


On Thu, Jul 1, 2010 at 2:54 PM, Jonathan Greenberg
<greenberg at ucdavis.edu> wrote:
> Rhelpers:
>
> How do I get R to evaluate a string, as if it was an R statement, e.g.:
>
> a=3
> b=2
> operator="-"
> statement_string=paste(a,operator,b,sep="")
>
> --j
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>



-- 
Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles
http://www.joshuawiley.com/